When I compiled chromium latest version from https://chromium.googlesource.com/chromium/src.git on loongson3a platform(mips64el architecture), occurs following errors:
[2587/25191] CC obj/third_party/angle/src/vulkan_support/vulkan_loader/debug_report.o
FAILED: obj/third_party/angle/src/vulkan_support/vulkan_loader/debug_report.o
gcc -MMD -MF obj/third_party/angle/src/vulkan_support/vulkan_loader/debug_report.o.d -DV8_DEPRECATION_WARNINGS -DUSE_UDEV -DUSE_AURA=1 -DUSE_PANGO=1 -DUSE_CAIRO=1 -DUSE_GLIB=1 -DUSE_NSS_CERTS=1 -DUSE_X11=1 -DNO_TCMALLOC -DDISABLE_NACL -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FORTIFY_SOURCE=2 -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DVULKAN_NON_CMAKE_BUILD -DSYSCONFDIR=\"/etc\" -DFALLBACK_CONFIG_DIRS=\"/etc/xdg\" -DFALLBACK_DATA_DIRS=\"/usr/local/share:/usr/share\" -DVK_USE_PLATFORM_XCB_KHR -DVK_USE_PLATFORM_XCB_KHX -DLAYERS_SOURCE_PATH=\"angledata\" -DDEFAULT_VK_LAYERS_PATH=\".\" -DAPI_NAME=\"Vulkan\" -DHAVE_SECURE_GETENV -I../.. -Igen -I../../third_party/vulkan-validation-layers/src/include -I../../third_party/vulkan-validation-layers/src/loader -Igen/third_party/angle/src/vulkan_support/angle/vulkan -Igen/third_party/angle/src/vulkan_support/angle/vulkan -I../../third_party/vulkan-validation-layers/src/include -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -funwind-tables -fPIC -pipe -mips64r2 -Wa,-mips64r2 -pthread -Wall -Wno-unused-local-typedefs -Wno-maybe-uninitialized -Wno-missing-field-initializers -Wno-unused-parameter -Os -fno-ident -fdata-sections -ffunction-sections -fomit-frame-pointer -g0 -fvisibility=hidden -Wno-unused-function -Wno-ignored-attributes -c ../../third_party/vulkan-validation-layers/src/loader/debug_report.c -o obj/third_party/angle/src/vulkan_support/vulkan_loader/debug_report.o
../../third_party/vulkan-validation-layers/src/loader/debug_report.c: In function ‘debug_report_create_instance’中:
../../third_party/vulkan-validation-layers/src/loader/debug_report.c:50:5: error ：‘for’ loop initial declarations are only allowed in C99 or C11 mode
for (uint32_t i = 0; i < pCreateInfo->enabledExtensionCount; i++) {
^
../../third_party/vulkan-validation-layers/src/loader/debug_report.c:50:5: Notes ：use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
../../third_party/vulkan-validation-layers/src/loader/debug_report.c: In function ‘util_CreateDebugReportCallbacks’中:
../../third_party/vulkan-validation-layers/src/loader/debug_report.c:235:5: error ：‘for’ loop initial declarations are only allowed in C99 or C11 mode
for (uint32_t i = 0; i < num_callbacks; i++) {
^
../../third_party/vulkan-validation-layers/src/loader/debug_report.c:238:13: error ：‘for’ loop initial declarations are only allowed in C99 or C11 mode
for (uint32_t j = 0; j < i; j++) {
^
../../third_party/vulkan-validation-layers/src/loader/debug_report.c: In function ‘util_DestroyDebugReportCallbacks’中:
../../third_party/vulkan-validation-layers/src/loader/debug_report.c:249:5: error ：‘for’ loop initial declarations are only allowed in C99 or C11 mode
for (uint32_t i = 0; i < num_callbacks; i++) {
^

loongson3a gcc version:
gcc -v
COLLECT_GCC=/usr/bin/gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/mips64el-redhat-linux/4.9.3/lto-wrapper
Targets：mips64el-redhat-linux
Configures：../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --enable-multilib --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-arch=loongson3a --enable-languages=c,c++,objc,obj-c++,fortran,go,lto --enable-plugin --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.9.3/obj-mips64el-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.9.3/obj-mips64el-redhat-linux/cloog-install --enable-gnu-indirect-function --with-long-double-128 --build=mips64el-redhat-linux
Thread Model：posix
gcc version 4.9.3 20150626 (Red Hat 4.9.3-5) (GCC)